A new complex Mn(Htpc)2(H2O)2(1, Htpc = 5-(trifluoromethyl)pyridine-2-carboxylic acid) has been synthesized and characterized by elemental analysis, IR, TG and single-crystal X-ray diffraction. 1 belongs to triclinic ...A new complex Mn(Htpc)2(H2O)2(1, Htpc = 5-(trifluoromethyl)pyridine-2-carboxylic acid) has been synthesized and characterized by elemental analysis, IR, TG and single-crystal X-ray diffraction. 1 belongs to triclinic system, space group P■ with a = 5.0885(10), b = 6.5574(13), c = 14.016(3) ?, β = 90.67(3)o, V = 436.34(17) ?3, Z = 1, Dc = 1.793 g·cm-3, μ = 0.855 mm-1, Mr = 471.18, F(000) = 235, the final R = 0.0454 and wR = 0.1134 for 1998 observed reflections with I > 2σ(I). The Mn(Ⅱ) ion is coordinated by two N and two O atoms from two Htpc as well as two O atoms from two coordinated water molecules, forming a 0D motif with distorted octahedral coordinate geometry. The adjacent 0D units are linked into 1D chains through hydrogen bond O(1W)–H(1 WB)···O(2), and via the O(1 W)–H(1 WA)···O(1) hydrogen bond the neighboring 1D chains are connected into a 2D supramolecular layer. Moreover, the interactions between the ligand and its complex with CT-DNA were studied by EtBr fluorescence probe, which suggested that these compounds bind to CT-DNA through an intercalation mode. The binding constants were 0.41 and 0.64 for Htpc and complex 1, respectively. It indicates that the interaction between complex 1 and CT-DNA is stronger than Htpc.展开更多
The title Mn(Ⅱ) coordination polymer,poly{[heptaaqua-(μ4-bi-phenyl-3,3?,5,5?-tetracarboxylate)-bimanganese(Ⅱ)] pentahydrate},[Mn_2(bpta)(H_2O)_7]_n·5n H_2O(I),is crystallized from a mixture of bi...The title Mn(Ⅱ) coordination polymer,poly{[heptaaqua-(μ4-bi-phenyl-3,3?,5,5?-tetracarboxylate)-bimanganese(Ⅱ)] pentahydrate},[Mn_2(bpta)(H_2O)_7]_n·5n H_2O(I),is crystallized from a mixture of biphenyl-3,3?,5,5?-tetracarboxylic acid(H_4bpta) and MnCl_2·4H_2O in waterethanol under room temperature. Its asymmetric unit consists of one and two halves of crystallographically independent Mn(Ⅱ) cations,one fully deprotonated H4 bpta ligand,seven coordinated water molecules and five solvent water as guest molecules. In I,each Mn(Ⅱ) atom is octahedrally coordinated by six oxygen atoms from bpta^(4-) anions and coordinated water molecules. In the Mn(Ⅱ) cations,one half Mn(Ⅱ) ion of them located at a 2-fold axis generating a trinuclear [Mn_3(H_2O)_2(RCOO)_2] linker by μ1,1-O(water) and μ1,3-O,O?(carboxylate) bridges and another half Mn(Ⅱ) ion with an inversion is a mononuclear linker. These neighbouring trinuclear and mononuclear Mn(Ⅱ) cations are linked together by biphenyl-3,3?,5,5?-tetracarboxylates to form a three-dimensional framework with a(42.84) topology of a(4,4)-connected net,in which the positions of the trinuclear [Mn_3(H_2O)_2(R-COO)_2] linker as a 4-connector linking four bpta^(4-) ligands in I reproduce an eagle-shaped arrangement. The polymeric structure exhibits a water channel with an accessible void of 797.1 ?~3,amounting to 15.7% of the total unit-cell volume. Each of the cavities in the network is occupied by solvent water molecules.展开更多
Furan carboxylic acids are important building blocks in polymer and fine chemical industries. In this work, a simple substrate adaptation strategy was applied to improve the catalytic performances of Comamonas testost...Furan carboxylic acids are important building blocks in polymer and fine chemical industries. In this work, a simple substrate adaptation strategy was applied to improve the catalytic performances of Comamonas testosteroni SC1588 cells for the synthesis of various furan carboxylic acids. It was found that biocatalytic synthesis of 5-hydroxymethyl-2-furancarboxylic acid(HMFCA) was substantially promoted by adding histidine and increasing cell concentrations. HMFCA was produced in a quantitative yield from200 m M HMF in 24 h. Besides, the HMFCA yields of 71%–81% were achieved with the substrate concentrations up to 250–300 m M. It was firstly found that 4-tert-butylcatechol(TBC), as the stabilizer present in HMF, exerted a significantly detrimental effect on whole-cell catalytic synthesis of HMFCA at high substrate concentrations(more than 130 m M). In addition, a variety of furan carboxylic acids such as2-furoic acid, 5-methyl-2-furancarboxylic acid and 5-methoxymethyl-2-furancarboxylic acid were synthesized with the yields up to 98%.展开更多
基金Supported by the Scientific Research Foundation of Higher Education Institutions of Ningxia(No.NGY2017004)the National Natural Science Foundation of China(Nos.21763022 and 50564043)the Major Innovation Projects for Building First-class Universities in China’s Western Region(No.ZKZD2017003)
文摘A new complex Mn(Htpc)2(H2O)2(1, Htpc = 5-(trifluoromethyl)pyridine-2-carboxylic acid) has been synthesized and characterized by elemental analysis, IR, TG and single-crystal X-ray diffraction. 1 belongs to triclinic system, space group P■ with a = 5.0885(10), b = 6.5574(13), c = 14.016(3) ?, β = 90.67(3)o, V = 436.34(17) ?3, Z = 1, Dc = 1.793 g·cm-3, μ = 0.855 mm-1, Mr = 471.18, F(000) = 235, the final R = 0.0454 and wR = 0.1134 for 1998 observed reflections with I > 2σ(I). The Mn(Ⅱ) ion is coordinated by two N and two O atoms from two Htpc as well as two O atoms from two coordinated water molecules, forming a 0D motif with distorted octahedral coordinate geometry. The adjacent 0D units are linked into 1D chains through hydrogen bond O(1W)–H(1 WB)···O(2), and via the O(1 W)–H(1 WA)···O(1) hydrogen bond the neighboring 1D chains are connected into a 2D supramolecular layer. Moreover, the interactions between the ligand and its complex with CT-DNA were studied by EtBr fluorescence probe, which suggested that these compounds bind to CT-DNA through an intercalation mode. The binding constants were 0.41 and 0.64 for Htpc and complex 1, respectively. It indicates that the interaction between complex 1 and CT-DNA is stronger than Htpc.
基金supported by the National Natural Science Foundation of China(No.21571118)
文摘The title Mn(Ⅱ) coordination polymer,poly{[heptaaqua-(μ4-bi-phenyl-3,3?,5,5?-tetracarboxylate)-bimanganese(Ⅱ)] pentahydrate},[Mn_2(bpta)(H_2O)_7]_n·5n H_2O(I),is crystallized from a mixture of biphenyl-3,3?,5,5?-tetracarboxylic acid(H_4bpta) and MnCl_2·4H_2O in waterethanol under room temperature. Its asymmetric unit consists of one and two halves of crystallographically independent Mn(Ⅱ) cations,one fully deprotonated H4 bpta ligand,seven coordinated water molecules and five solvent water as guest molecules. In I,each Mn(Ⅱ) atom is octahedrally coordinated by six oxygen atoms from bpta^(4-) anions and coordinated water molecules. In the Mn(Ⅱ) cations,one half Mn(Ⅱ) ion of them located at a 2-fold axis generating a trinuclear [Mn_3(H_2O)_2(RCOO)_2] linker by μ1,1-O(water) and μ1,3-O,O?(carboxylate) bridges and another half Mn(Ⅱ) ion with an inversion is a mononuclear linker. These neighbouring trinuclear and mononuclear Mn(Ⅱ) cations are linked together by biphenyl-3,3?,5,5?-tetracarboxylates to form a three-dimensional framework with a(42.84) topology of a(4,4)-connected net,in which the positions of the trinuclear [Mn_3(H_2O)_2(R-COO)_2] linker as a 4-connector linking four bpta^(4-) ligands in I reproduce an eagle-shaped arrangement. The polymeric structure exhibits a water channel with an accessible void of 797.1 ?~3,amounting to 15.7% of the total unit-cell volume. Each of the cavities in the network is occupied by solvent water molecules.
基金financially supported by the National Natural Science Foundation of China(21676103)the Natural Science Foundation of Guangdong Province(2017A030313056)the Science and Technology Project of Guangzhou City(201804010179)。
文摘Furan carboxylic acids are important building blocks in polymer and fine chemical industries. In this work, a simple substrate adaptation strategy was applied to improve the catalytic performances of Comamonas testosteroni SC1588 cells for the synthesis of various furan carboxylic acids. It was found that biocatalytic synthesis of 5-hydroxymethyl-2-furancarboxylic acid(HMFCA) was substantially promoted by adding histidine and increasing cell concentrations. HMFCA was produced in a quantitative yield from200 m M HMF in 24 h. Besides, the HMFCA yields of 71%–81% were achieved with the substrate concentrations up to 250–300 m M. It was firstly found that 4-tert-butylcatechol(TBC), as the stabilizer present in HMF, exerted a significantly detrimental effect on whole-cell catalytic synthesis of HMFCA at high substrate concentrations(more than 130 m M). In addition, a variety of furan carboxylic acids such as2-furoic acid, 5-methyl-2-furancarboxylic acid and 5-methoxymethyl-2-furancarboxylic acid were synthesized with the yields up to 98%.